Lifter roof tank



ct. 25, 1949. I H. c, BOARDMAN A 29485557 LIFTER ROOF TANK Filed April 17, 1946 Sheets-Sheet l l n l l Oct. 25, 1949. v H. c. BOARDMAN l l 2,485,557

LIFTER ROOF TANK Filed April 17, 194s 2 Sheets-sheet 2 j v/067;? 074 QW" par mf; W5.

Patented Oct. 25, 1.949

UNITED STATES PATENT OFFICE LIFTER ROOF TANK Harry C. Boardman, Chicago, Ill., assignor to Chicago Bridge & Iron Company Application April 17, 1946, Serial No. 662,725

4 Claims. l

This invention relates to a lifter roof tank for the storage of gas or mixtures of gas and liquid, and relates particularly to a means for sealing the area between the roof and the shell of the tank.

In lifter roof tanks the roof rises and falls by the pressure of gas within the tank. In effect, therefore, the roof floats on top of the gas. It it necessary that some form of sealing means be provided between the roof and the shell of the tank so as to prevent the escape of gas. This sealing means must be exible so as to accommodate itself to the various positions of the roof.

The sealing means `of the present invention comprises broadly a downwardly extending member attached to the roof and spaced inwardly from the shell, and a iiexible member attached to the downwardly extending member and to the shell. The downwardly extending member has the same shape as the shell, but it is smaller in diameter. There are preferably provided brackets around the inside of the shell upon which the downwardly extending member rests when the roof is in its lowest position. The flexible sealing member preferably extends upwardly from the downwardly extending member when the roof is in its lowest position, so that the sealing member will .be backed up at substantially all times by the downwardly extending member or other portions of the roof structure.

The invention will be described as related to the embodiment set out in the accompanying drawings. O-f the drawings Fig. 1 is an elevation of a lifter roof tank embodying the invention, with the drawings being partially in section; Fig. 2 is a fragmentary vertical section through the top edge of the shell of the tank and the outer edge .of the roof; Fig. 3 is a View similar to Fig. 2 showing the roof in its highest position; and Figs. 4 and 5 are views similar to Figs. 2 and 3 showing a wider seal construction.

The lifter roof tank shown in the drawings comprises a shell Il] and a roof I I. A downwardly extending weather skirt I2 is attached to the roof outside of the shell I0. There is also provided a downwardly extending cylindrical section I3 at'- tached to the roof and positioned inside the shell I0. At the bottom of the cylindrical section I3 there is attached an upwardly extending flexible sealing member I4 having its outer edge attached to the top of the shell I0.

The flexible sealing member I4 is of greater width than the shortest distance between the bottom of the cylindrical section I3 and the top of the shell I when the roof is in its lowest posiber is attached to the bottom of the `cylindrical section by means of a lwasher bar I5 and spaced bolts I6. The outer edge of the flexible sealing member is attached to an angle member II fastened on the outer top edge of the shell I0 and is attached by means of a second washer bar I8 and spaced bolts I9.

On the inner surface of the shell I0 there are located a number of brackets upon which the cylindrical section is supported when the roof is in its lowest position.

The iiexible sealing member I4 is preferably a fabric impregnated with a exible impervious weather skirt' I2 and the cylindrical section I3, as

well as the cylindrical section I3. Such a construction is shown in Figs. 4 and 5. When the roof is in its highest position as shown in Fig. 5 the seal is backed up throughout substantially its entire width by the cylindrical section I3, the weather skirt I2 and the portion of the roof between the members I2 and I3. When the roof is in lowest position, as shown in Fig. 4, the seal forms a loop 2| extending downwardly into the space between the shell Ill and the weather skirt I2. Proper positioning of the brackets 20 serve to prevent pinching of the seal when the roof is in its lowest position.

Having described my invention as related to the embodiment set out in the accompanying drawings, it is my intention that the invention be not limited .by the details of description unless otherwise specilied, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

I claim:

1.- In a lifter roof tank comprising a shell and a movable roof thereover, sealing means comprising a downwardly extending cylindrical member attached to the roof and spaced inwardly from the shell, a weatherskirt attached to the roof and extending downwardly therefrom on the outside of the shell, a flexible sealing member extending from the downwardly extending member to the shell, said sealing member being sufficiently wide ber attached to thesroof, and :spa-ced iiniwardlyf from the-'Shelli af'oylindrical weatherfski'rt attached to the roof and extending downwardly on the outside of the shell, a flexible sealing meme-- ber extending from the lower part of the.-fdown-.-

wardly extending member to the upper part of the shell, said sealing member lbeingfsuieien-tly- -VY wide as to be substantially entirely backed up "byh the cylindrical member, the weather ,skirtiandm the portion of the roof between the .cylindrical member and the weather skirt in al1 positions-0f the roof, and stop members on the shell for determiningy theflowestzpositiorrfof the roof lwherein saidnportion :of :the root-'isl spaced above the top ofi the` shell..

3.,Tl'i`e/sliterA roofxtanlr of4 claim 2 in which the 25 Number inner sidewall .on the cshell 4 and upon' vwhich the stoplmemb'ers'. comprise brackets attached .tol the cylindrical member rests when the roof is in its lowest position.

4. In a lifter roof tank comprising a shell and a movable roof thereover, sealing means comprising a downwardly extending cylindrical member attached to the roof and spaced inwardly from the shell, a cylindrical weather skirt attached to the roof and extending downwardly ionv the outside of'the shell, anda lexiblesealing member' extendingv from"n the lower' part of the downwardly extending member to the upper part ofthe shell, said sealing member 4being sufficiently wide as .to be backed up .by the cylindrical member and the weather skirt with said sealing memyberebeirigsubstantially out of Contact with the REFERENCES CITED The'following vreierencesare vof record in thek l'e "of-this patent:

UNITED STATES PATENTS Name Date 2,337,286v Wiggins Dec. 21, 1943 

